Resin compositions comprising a polyarylate and a poly(alkylene-phenylene ester) are known, which can give molded articles having an excellent balance between heat distortion resistance and chemical resistance. However, these compositions have a drawback that their impact resistance is generally low and this poses practical problems.
As an expedient for improving the poor impact resistance, incorporation of a glycidyl ester group-containing copolymer produced from an .alpha.-olefin and a glycidyl ester of an .alpha.,.beta.-unsaturated acid into a composition of the above kind is disclosed in JP-A-61-26657. (The term "JP-A", as used herein means an "unexamined published Japanese patent application".) This expedient, however, is defective in that almost no improvement is attained in notched Izod impact strength at a low temperature (-30.degree. C.), although the room-temperature notched Izod impact strength of the composition is surely improved. In addition, the thus-modified composition has a practically serious problem that it shows significantly impaired flowability during molding.